1. Field of the Invention
The present invention relates to an optical element holder used to take stereo images with two cameras, and to a stereoscopic imaging device utilizing the holder.
2. Description of the Background Art
In order photograph stereo images, to date a stereoscopic imaging device 900 as shown in FIG. 11 has at times been used. The stereoscopic imaging device 900 includes a left-eye camera 910, a right-eye camera 920, and a platelike semi-reflective mirror 930. The semi-reflective mirror 930 passes one portion of light incident on the mirror and reflects the remaining portion. The left-eye camera 910 shoots the optical image having passed through the semi-reflective mirror 930, and the right-eye camera 920 shoots the optical image having been reflected by the semi-reflective mirror 930. Furthermore, the left-eye camera 910 can move in the direction perpendicular to the drawing sheet. The stereo base between the left-eye camera 910 and the right-eye camera 920 is thereby changed to adjust the left-eye and right-eye parallaxes.
Because the semi-reflective mirror 930 described above is platelike in form, if the semi-reflective mirror 930 is of large size, it will deflect under its own weight. This causes distortion of the optical image and displacement along the way of the optical path to occur in light having passed through or been reflected by the semi-reflective mirror 930. A consequent problem is that taking highly accurate stereo images is made difficult. It is to be noted that Japanese Laid-open Patent Publication No. 2004-312545 discloses technology relevant to the present application.